28478690 has 16 divisors (see below), whose sum is σ = 51400440. Its totient is φ = 11360640.

The previous prime is 28478683. The next prime is 28478693. The reversal of 28478690 is 9687482.

It can be written as a sum of positive squares in 4 ways, for example, as 8649481 + 19829209 = 2941^2 + 4453^2 .

It is a super-2 number, since 2×28478690² = 1622071568232200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28478693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 230 + ... + 7550.

Almost surely, 2^28478690 is an apocalyptic number.

28478690 is a deficient number, since it is larger than the sum of its proper divisors (22921750).

28478690 is a wasteful number, since it uses less digits than its factorization.

28478690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7717.

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 28478690 is about 5336.5428884251. The cubic root of 28478690 is about 305.3795865151.

The spelling of 28478690 in words is "twenty-eight million, four hundred seventy-eight thousand, six hundred ninety".